Perhaps it's because we sometimes take the things we see around us for granted and a technical drawing of its design shows the effort that went into it that I find these Nasa drawings so interesting. That in addition to the labels saying what things do. With that in mind, i included an diagram which isn't really a blueprint, from a Apollo 15 press kit showing how they unpacked the lunar rover – for some reason I always wondered how they did that. I also cheated with a couple of NASA project images that aren't from NASA to show how other companies were involved – such as Lockheed's Hubble Telescope and Boeing's drawings of the Saturn V configuration.